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1.
Molecules ; 27(22)2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36431881

RESUMEN

Brazil's production and consumption of açai pulp (Euterpe oleracea) occur on a large scale. Most of the fruit is formed by the pit, which generates countless tons of residual biomass. A new purpose for this biomass, making its consumption highly sustainable, was presented in this study, where activated carbon (AC) was produced with zinc chloride for later use as an adsorbent. AC carbon formed by carbon and with a yield of 28 % was satisfactorily used as an adsorbent in removing the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). Removal efficiency was due to the highly porous surface (Vp = 0.467 cm3 g-1; Dp = 1.126 nm) and good surface área (SBET = 920.56 m2 g-1). The equilibrium data fit the Sips heterogeneous and homogeneous surface model better. It was observed that the increase in temperature favored adsorption, reaching a maximum experimental capacity of 218 mg g-1 at 328 K. The thermodynamic behavior indicated a spontaneous, favorable, and endothermic behavior. The magnitude of the enthalpy of adsorption was in agreement with the physical adsorption. Regardless of the herbicide concentration, the adsorbent displayed fast kinetics, reaching equilibrium within 120 min. The linear driving force (LDF) model provided a strong statistical match to the kinetic curves. AC with zinc chloride (ZnCl2), created from leftover açai biomass, is a potential alternative as an adsorbent for treating effluents containing 2,4-D.


Asunto(s)
Euterpe , Herbicidas , Porosidad , Frutas , Carbón Orgánico , Fenoxiacetatos , Semillas , Ácido 2,4-Diclorofenoxiacético
2.
FASEB J ; 26(10): 4035-44, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22744867

RESUMEN

Normal pregnancy involves dramatic remodeling of the uterine vasculature, with abnormal vascular adaptations contributing to pregnancy diseases such as preeclampsia. The peptide hormone relaxin is important for the renal and systemic hemodynamic adaptations to pregnancy, and has been shown to increase arterial compliance and outward hypertrophic remodeling. Therefore, we investigated the possibility that relaxin acts on its receptor, RXFP1, to mediate uterine artery compliance in late pregnancy and increase uterine blood flow velocity in rats. RXFP1 was predominantly localized to the tunica media vascular smooth muscle cells in the uterine artery, although receptors were also detected in endothelial cells. Highest expression of Rxfp1 in the uterine artery occurred in estrus and early pregnancy. Isolated uterine arteries from late pregnant rats treated with a monoclonal antibody against circulating relaxin (MCA1) had significantly increased vessel wall stiffness compared with controls, with no reduction in wall thickness. Chronic infusion of relaxin (4 µg/h, osmotic minipump) for 5 d in nonpregnant rats significantly increased uterine artery blood flow velocity. Overall, these data demonstrate a functional role for relaxin in mediating uterine artery compliance in pregnant rats, which may be necessary to maintain adequate uterine blood flow to the uterus and placenta.


Asunto(s)
Relaxina/metabolismo , Arteria Uterina/metabolismo , Útero/irrigación sanguínea , Útero/metabolismo , Animales , Anticuerpos Neutralizantes/farmacología , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Inmunohistoquímica , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Embarazo , Preñez , Ratas , Ratas Endogámicas WKY , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Péptidos/metabolismo , Relaxina/antagonistas & inhibidores , Arteria Uterina/efectos de los fármacos , Útero/efectos de los fármacos
3.
Mol Pharm ; 10(5): 1836-44, 2013 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-23510151

RESUMEN

The concept of gene therapy is promising; however, the perceived risks and side effects associated with this technology have severely dampened the researchers' enthusiasm. Thus, the development of a nonviral gene vector without immunological effects and with high transfection efficiency is necessary. Currently, most nonviral vectors have failed to achieve the in vivo transfection efficiencies of viral vectors due to their toxicity, rapid clearance, and/or inappropriate release rates. Although our previous studies have successfully demonstrated the controlled-release of plasmid DNA (pDNA) polyplexes encapsulated into nanoparticles formulated with l-tyrosine polyphosphate (LTP-pDNA nanoparticles), the in vivo transfection capabilities and immunogenicity of this delivery system have yet to be examined. Thus, we evaluate LTP-pDNA nanoparticles in an in vivo setting via injection into rodent uterine tissue. Our results demonstrate through X-gal staining and immunohistochemistry of uterine tissue that transfection has successfully occurred after a nine-day incubation. In contrast, the results for the control nanoparticles show results similar to those of shams. Furthermore, reverse transcriptase polymerase chain reaction (RT-PCR) from the injected tissues confirms the transfection in vivo. To examine the immunogenicity, the l-tyrosine polyphosphate (LTP) nanoparticles have been evaluated in a mouse model. No significant differences in the activation of the innate immune system are observed. These data provide the first report for the potential use of controlled-release nanoparticles formulated from an amino acid based polymer as an in vivo nonviral vector for gene therapy.


Asunto(s)
Técnicas de Transferencia de Gen , Nanopartículas/química , Organofosfatos/química , Polímeros/química , Animales , Femenino , Terapia Genética , Vectores Genéticos , Inmunidad Innata , Ratones , Nanocápsulas/administración & dosificación , Nanocápsulas/química , Nanopartículas/administración & dosificación , Organofosfatos/administración & dosificación , Organofosfatos/inmunología , Plásmidos/administración & dosificación , Plásmidos/genética , Polímeros/administración & dosificación , Ratas Endogámicas WKY , Transfección , Útero/inmunología , Útero/metabolismo
4.
Stress ; 14(1): 33-41, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20666653

RESUMEN

Increased sympathetic nervous system (SNS) activity, testosterone, and spontaneously hypertensive rat Y chromosome (SHR Yc) play a role in a genetic model of hypertension. Male rats with the SHR Yc and Wistar-Kyoto (WKY) autosomes (denoted SHR/y) exhibit these characteristics when compared to rats with the WKY Yc and WKY autosomes (denoted WKY). We hypothesized that chronic social stress will increase blood pressure and SNS activity more in SHR/y males compared to WKY males, resulting in increased myogenic reactivity along with decreased vasoconstriction of small mesenteric arteries. SHR/y and WKY males were housed in strain- specific colonies (10 males with 10 females) or as controls (10 males). Systolic blood pressure (SBP) and blood samples were collected prior to termination. Second-order mesenteric arteries were studied using a pressure arteriograph in which myogenic reactivity and phenylephrine (PE) responsiveness were measured. SHR/y colony SBP, and circulating norepinephrine and testosterone concentrations were elevated compared to control and WKY colony males (p < 0.05). Mesenteric artery myogenic reactivity was increased in SHR/y colony males (p < 0.001). Mesenteric arteries from SHR/y colony males exhibited a significant decrease in PE-induced constriction. Colony social stress elevated both SNS activity and testosterone level which may be responsible for the increased mesenteric artery myogenic reactivity, and SBP as noted in SHR/y males.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Vasoconstricción/efectos de los fármacos , Animales , Aglomeración , Vivienda para Animales , Masculino , Arterias Mesentéricas/fisiología , Norepinefrina/sangre , Fenilefrina/farmacología , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Estrés Psicológico , Testosterona/sangre , Cromosoma Y
5.
Clin Exp Hypertens ; 33(2): 124-32, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21271819

RESUMEN

Androgens interact with catecholamines in the central nervous system (CNS) to regulate many physiological processes including blood pressure (BP). To test the hypothesis that testosterone (T) and 5a-dihydrotestosterone (DHT) modulate CNS catecholamines and BP through androgen receptor (AR)-dependent and independent mechanisms, we used the testicular feminized male (Tfm) rat. Females that carry the AR mutation (Tfm mutation) on the X chromosome were bred with spontaneously hypertensive rat (SHR) males. The normal AR male and Tfm offspring were divided into groups: control, castrated, castrated, and T or (DHT) replacement. In both AR normal and Tfm males, BP was reduced by castration, but T restored BP in both groups. In the amygdale, castration decreased dopamine (DA) in both strains and both T and DHT restored it. In the bed nucleus of the stria terminalis castration increased DA which was further increased by DHT and reduced to normal by T in both strains. In the frontal cortex, castration reduced DA content in both strains but only T restored it to normal in SHR but not in Tfm. Brain norepinephrine (NE) content showed a significant strain effect for the preoptic area (POA), but no treatment effect. Although castration did not change NE in the amygdala or POA in either strain, both T and DHT increased NE in the Tfm castrates. Blood pressure was influenced by T manipulation and correlated most significantly with DA content in the amygdala, frontal cortex, and stria terminalis. These data demonstrate an action of androgen on brain catecholamines and BP, which is independent of the classic androgen receptor.


Asunto(s)
Síndrome de Resistencia Androgénica/fisiopatología , Andrógenos/fisiología , Presión Sanguínea/fisiología , Encéfalo/fisiopatología , Catecolaminas/fisiología , Síndrome de Resistencia Androgénica/genética , Animales , Dihidrotestosterona/administración & dosificación , Modelos Animales de Enfermedad , Femenino , Masculino , Orquiectomía , Ratas , Ratas Endogámicas SHR , Ratas Mutantes , Receptores Androgénicos/genética , Testosterona/administración & dosificación , Testosterona/fisiología
6.
J Am Mosq Control Assoc ; 25(2): 208-9, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19653506

RESUMEN

The geographical distributions of Aedes aegypti, Culex apicinus, Cx. educator, Cx. interfor, Cx. quinquefasciatus, Mansonia humeralis, Ma. indubitans, and Psorophora albigenu/varipes are extended, including new records for 2 provinces.


Asunto(s)
Culicidae/clasificación , Insectos Vectores/clasificación , Animales , Argentina , Biodiversidad , Culicidae/fisiología , Geografía , Insectos Vectores/fisiología , Control de Mosquitos , Densidad de Población
7.
Sci Total Environ ; 668: 988-995, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-31018477

RESUMEN

The oxygen transfer rate (OTR) has a significant impact on the design and operation of vertical flow constructed wetlands (VFCWs) intended for organic matter removal and nitrification. Despite its key role, the information on real oxygen input in VFCWs is limited, being usually estimated by mass balance (stoichiometry), through which is calculated only the oxygen consumption rate (OCR). In this study, for the first time, the gas tracer method was applied to evaluate the oxygen transfer capacity of a real-scale VFCW (24.5 m2) applied to the treatment of domestic wastewater. Propane was used as tracer. The OCR and the OTR were evaluated in VFCW under hydraulic loading rates (HLR) of 60, 90, and 120 mm d-1 corresponding to recirculation rations of 0%, 50%, and 100%. The OTR in standard conditions (20 °C) ranged from 120 to 176 g O2 m-2 d-1. The highest OTR was found for the lowest HLR. For the operating conditions tested, the OTR obtained with gas tracer were higher than the OCR calculated by stoichiometry in VFCW, which ranged from 20.6 to 27.8 g O2 m-2 d-1. Besides, the OTR were sufficient to satisfy the VFCW oxygen demand for organic matter removal and nitrification. These results show that the gas tracer method for OTR determination may allow advances on the understanding of treatment processes and on the design of new VFCWs since its treatment performance requires aerobic conditions.

8.
Endocrinology ; 147(11): 5126-31, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16873529

RESUMEN

During early pregnancy, there are marked increases in cardiac output (CO) and global arterial compliance (AC), as well as decreases in systemic vascular resistance (SVR). We recently reported that administration of recombinant human relaxin to nonpregnant female rats elicits changes in systemic hemodynamics and arterial mechanical properties similar to those observed during normal pregnancy. In the present study, we directly tested whether endogenous relaxin mediates the cardiovascular adaptations of pregnancy by neutralizing circulating relaxin with monoclonal antibodies during early gestation. Relaxin neutralizing antibodies were administered daily, beginning on d 8 of rat gestation, to block the functional effects of circulating relaxin. Systemic hemodynamics and arterial properties were assessed between gestational d 11 and 15 using techniques we have previously reported. Pregnant rats administered the neutralizing antibodies failed to exhibit the gestational increases in stroke volume, CO, and global AC or decreases in SVR that were observed in control pregnant rats administered an irrelevant antibody against fluorescein or PBS. In fact, in the pregnant rats administered the relaxin neutralizing antibodies, cardiovascular parameters were not statistically different from those in virgin rats. Interestingly, small renal and first-order mesenteric arteries isolated from midterm pregnant rats administered either relaxin-neutralizing or control antibodies did not exhibit any changes in passive mechanical properties compared with virgin rats. These findings indicate that circulating relaxin mediates the transition of the systemic circulation from the virgin to the pregnant state in the gravid rat model, suggesting a potential role for aberrant relaxin regulation in abnormal pregnancies wherein these cardiovascular adaptations are inadequate or excessive.


Asunto(s)
Arterias/fisiología , Preñez/fisiología , Relaxina/fisiología , Vasodilatación , Animales , Adaptabilidad , Femenino , Embarazo , Ratas , Ratas Long-Evans
9.
Cancer Inform ; 13(Suppl 5): 129-40, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25991908

RESUMEN

Whole transcriptome shotgun sequencing (RNA-Seq) is a useful tool for analyzing the transcriptome of a biological sample. With appropriate statistical and bioinformatic processing, this platform is capable of identifying significant differences in gene expression within the transcriptome and permits pathway and network analyses to determine how these genes interact biologically. In this study, we examined gene expression in two lung adenocarcinoma cell lines (H358 and A459) that were treated with transforming growth factor-ß (TGF-ß) as a model for induction of the epithelial-to-mesenchymal transition (EMT), commonly associated with disease progression. We performed this study in order to illustrate a workflow for identifying interesting genes and processes that are regulated early in EMT and to determine their gene pathway/network relationships and regulation. With this, we identified 137 upregulated and 32 downregulated genes common to both cell lines after TGF-ß treatment that represent components of multiple canonical pathways and biological networks associated with the induction of EMT. These findings were also verified against reposited Affymetrix U133a expression profiles from multiple trials examining metastatic progression in patient cohorts (n = 731 total) to further establish the clinical relevance and translational significance of the model system. Together, these findings help validate the relevance of the TGF-ß model for the study of EMT and provide new insights into early events in EMT.

10.
Biol Sex Differ ; 3(1): 1, 2012 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-22214247

RESUMEN

BACKGROUND: Testosterone (T) and the sympathetic nervous system each contribute to the pathology of hypertension. Altered blood vessel reactivity is also associated with the pathology of high blood pressure. The purpose of this study was to examine the effects of T manipulation in the regulation of resistance-sized blood vessel reactivity. METHODS: Adult spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) male rats at 8 weeks of age were used. The rats were divided into groups consisting of gonadally intact controls (CONT), castrate with sham implant (CAST) and castrate with T implant (CAST + T) (n = 6 to 12 per group). Following a short-term period of T treatment (approximately 4 weeks), plasma norepinephrine (NE) and plasma T were assessed by performing high-performance liquid chromatography and RIA, respectively. Resistance-sized mesenteric artery reactivity was assessed on a pressurized arteriograph for myogenic reactivity (MYO), phenylephrine (PE) responsiveness and passive structural mechanics. RESULTS: SHR and WKY males exhibited similar physiological trends in T manipulation, with castration significantly lowering plasma T and NE and T replacement significantly increasing plasma T and NE. T manipulation in general resulted in significant alterations in MYO of second-order mesenteric arteries, with T replacement decreasing MYO in SHR (P < 0.05) compared to CONT, T replacement increasing MYO, and CAST decreasing MYO in WKY rats (P < 0.001) compared to CONT rats. Additionally, PE-induced constriction was significantly altered in both strains following T treatment, with the effective concentration of PE to constrict the vessel to 50% of the total diameter significantly increased in the CAST + T SHR compared to CONT (P < 0.05). Comparisons of passive structural mechanics between SHR and WKY treatment groups indicated in SHR a significantly increased wall-to-lumen ratio and decreased circumferential wall stress compared to WKY treatment groups. CONCLUSIONS: These data suggest that T and NE are involved in a complex interaction with both myogenic reactivity and structural alterations of resistance-sized blood vessels and that these factors likely contribute to the development and maintenance of hypertension.

11.
PLoS One ; 7(4): e35261, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22536361

RESUMEN

The centromere is a repeat-rich structure essential for chromosome segregation; with the long-term aim of understanding centromere structure and function, we set out to identify cotton centromere sequences. To isolate centromere-associated sequences from cotton, (Gossypium hirsutum) we surveyed tandem and dispersed repetitive DNA in the genus. Centromere-associated elements in other plants include tandem repeats and, in some cases, centromere-specific retroelements. Examination of cotton genomic survey sequences for tandem repeats yielded sequences that did not localize to the centromere. However, among the repetitive sequences we also identified a gypsy-like LTR retrotransposon (Centromere Retroelement Gossypium, CRG) that localizes to the centromere region of all chromosomes in domestic upland cotton, Gossypium hirsutum, the major commercially grown cotton. The location of the functional centromere was confirmed by immunostaining with antiserum to the centromere-specific histone CENH3, which co-localizes with CRG hybridization on metaphase mitotic chromosomes. G. hirsutum is an allotetraploid composed of A and D genomes and CRG is also present in the centromere regions of other AD cotton species. Furthermore, FISH and genomic dot blot hybridization revealed that CRG is found in D-genome diploid cotton species, but not in A-genome diploid species, indicating that this retroelement may have invaded the A-genome centromeres during allopolyploid formation and amplified during evolutionary history. CRG is also found in other diploid Gossypium species, including B and E2 genome species, but not in the C, E1, F, and G genome species tested. Isolation of this centromere-specific retrotransposon from Gossypium provides a probe for further understanding of centromere structure, and a tool for future engineering of centromere mini-chromosomes in this important crop species.


Asunto(s)
Gossypium/genética , Retroelementos/genética , Secuencias Repetidas Terminales/genética , Centrómero , Cromosomas de las Plantas/genética , Mapeo Contig , Genes de Plantas , Análisis de Secuencia de ADN , Secuencias Repetidas en Tándem
12.
Pregnancy Hypertens ; 2(2): 106-114, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22679605

RESUMEN

The etiology of preeclampsia remains unknown. However, a contributing factor to this hypertensive disease of pregnancy is a reduction in uterine perfusion pressure resulting in placental ischemia. Uterine arteries may be a major regulator of this process through changes in vascular reactivity and localized blood flow. The reduced uterine perfusion pressure (RUPP) pregnant rat is an established animal model of preeclampsia pathology. Pregnant Sprague Dawley rats were used for this investigation and subjected to RUPP or SHAM surgery on Day 14 of gestation. On Day 21 of gestation, animals were terminated and resistance-caliber uterine arteries were harvested and mounted on a pressurized arteriograph to examine myogenic reactivity, agonist induced vasodilation (methacholine and VEGF), and vasoconstriction (phenylephrine and U-46619). Resistance-caliber uterine arteries from RUPP animals exhibited increased myogenic reactivity and decreased vasodilation (methacholine and VEGF) compared to SHAM uterine arteries (p<0.05). Phenylephrine and U-46619 induced constriction was similar in uterine arteries between RUPP and SHAM rats. These results suggest that resistancecaliber uterine arteries from RUPP pregnant rats are altered to reflect a more constrictive phenotype which may play a role in the development of maternal hypertension demonstrated in these animals and thereby potentially in preeclampsia.

13.
Hypertens Pregnancy ; 30(1): 45-57, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-20818955

RESUMEN

OBJECTIVE: A central component of preeclampsia is a reduction in utero-placental perfusion. We tested the hypothesis that vascular reactivity of second - order mesenteric arteries would be increased in a pregnant rat with reduced uterine perfusion pressure (RUPP). METHODS: Pregnant 10-12 week old Sprague-Dawley rats underwent RUPP surgery on gestational day 14, and experiments were carried out on day 20. SHAM operated animals were used as controls. Resistance caliber mesenteric arteries (200-250 µm) were isolated, myogenic reactivity and responses to vasoconstrictor and vasodilator agonists were assessed utilizing a pressurized arteriograph system. RESULTS: RUPP resulted in maternal hypertension and reductions in fetal number and weight. Resistance caliber mesenteric arteries (200-250 µm) were isolated, myogenic reactivity and responses to vasoconstrictor and vasodilator agonists were assessed utilizing a pressurized arteriograph system. Myogenic reactivity responses were normalized as a percent change in vessel diameter from an initial diameter at 20 mmHg. The mesenteric arteries from RUPP animals exhibited a significant increase in myogenic reactivity compared to SHAM controls (p < 0.05). This increased myogenicity was reversed with prostaglandin inhibition, suggesting a role for a vasoconstrictor prostaglandin. In addition to alterations in myogenic reactivity, resistance-sized arteries from RUPP animals have decreased responses to nitric oxide (NO) as evidenced by decreases in responses to methacholine (ME; P < 0.05) and no change in myogenic reactivity after NO synthase blockade. CONCLUSION: RUPP alters the behavior of resistance caliber arteries to favor a more contractile phenotype with decreased in NO responses, which is similar to what is seen in preeclampsia.


Asunto(s)
Arterias Mesentéricas/fisiología , Músculo Liso Vascular/fisiología , Útero/irrigación sanguínea , Útero/fisiología , Animales , Femenino , Embarazo , Presión , Ratas , Ratas Sprague-Dawley
14.
Hypertens Pregnancy ; 30(2): 208-20, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-20846047

RESUMEN

BACKGROUND: The etiology of preeclampsia remains unclear. Animal modeling of preeclampsia has been useful; however, no model to date represents episodic changes in uteroplacental blood flow that may occur in preeclampsia. OBJECTIVE: To develop a gravid rat model characterized by episodic reductions in uteroplacental blood flow. METHOD: Pregnant Sprague Dawley rats were used and subjected to SHAM, reduced uterine perfusion pressure (RUPP), or aortic occlusion on gestational Day 14. Aortic occlusion surgery consisted of implantation of a silastic vascular occluder around the abdominal aorta and silver clips around the uterine-ovarian arteries. Aortic occlusion animals were subjected to five consecutive days of occlusion (40% reduction) each session lasting 1 h. On Day 21, maternal mean arterial pressure (MAP) and fetal morphology were assessed. For isolated blood vessels, resistance-sized mesenteric arteries were harvested and mounted on a pressure arteriograph. RESULT: Occluder animals experienced a 10 mmHg rise in MAP as compared to SHAM (p < 0.05), and RUPP MAP was significantly increased as compared to control subjects (p < 0.05). Pups from Occluder animals exhibited a decrease in fetal weight as compared to SHAM (p < 0.05), but an increase in fetal weight as compared to RUPP (p < 0.05). Myogenic reactivity of second-order mesenteric arteries increased in Occluder animals as compared to SHAM (p < 0.05), but were similar to that of RUPP. CONCLUSION: Episodic reductions in uteroplacental blood flow play a crucial role in the altered vascular reactivity seen in Occluder animals and may represent a new model to investigate the mechanisms associated with episodic reductions in uteroplacental blood flow in pathological pregnancies.


Asunto(s)
Hipertensión Inducida en el Embarazo/etiología , Placenta/irrigación sanguínea , Flujo Sanguíneo Regional/fisiología , Útero/irrigación sanguínea , Análisis de Varianza , Animales , Femenino , Hipertensión Inducida en el Embarazo/fisiopatología , Placenta/fisiopatología , Embarazo , Ratas , Ratas Sprague-Dawley , Útero/fisiopatología
15.
Gend Med ; 8(1): 40-52, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21497771

RESUMEN

BACKGROUND: Testosterone (T) and the androgen receptor (AR) are involved in mechanisms associated with hypertension and vessel reactivity. OBJECTIVE: To investigate T and the AR on blood vessel reactivity, testicular feminized male (TFM; AR deficient males) and normal androgen receptor (NAR) male rats were used. Therefore, if the functional AR is necessary for plasma T to regulate vessel responsiveness, TFM males will exhibit altered vessel function compared to NAR males. METHODS: Adult (16 weeks of age) TFM or NAR males were assigned to the following treatment groups: gonadal intact controls (CONT), castrate (CAST), or castrate with T replacement (CAST+T) with (n=8-10/group). RESULTS: Plasma T followed a consistent pattern with CAST+T elevated compared to CONT and CAST TFM and NAR males. In addition, CAST plasma T was significantly decreased compared to CONT and CAST+T in TFM and NAR males. In a similar manner for systolic blood pressure (SBP), CAST lowered SBP compared to CONT in both NAR and TFM. Following 8 weeks of treatment, second-order mesenteric artery responses to changes in intraluminal pressure (myogenic reactivity) were analyzed using a pressure arteriograph system. Both TFM (P < 0.05) and NAR (P < 0.05) CAST groups revealed a decrease in myogenic reactivity compared to CONT. Following T treatment the TFM CAST+T myogenic reactivity returned to CONT levels, whereas the NAR CAST+T myogenic reactivity increased a further 10%. CONCLUSION: The results of this study indicate that T differentially regulates mesenteric artery reactivity in TFM and NAR males. Our data also demonstrate that both AR and/or non-AR mediated mechanisms may partially contribute to SBP regulation.


Asunto(s)
Arterias Mesentéricas/fisiología , Desarrollo de Músculos , Músculo Liso Vascular/fisiología , Receptores Androgénicos/metabolismo , Testosterona/fisiología , Animales , Masculino , Arterias Mesentéricas/metabolismo , Músculo Liso Vascular/metabolismo , Ratas
16.
Hypertension ; 47(3): 454-60, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16432038

RESUMEN

Plasma ascorbic acid is decreased in women with the pregnancy disorder preeclampsia. We used a mutant strain of rats (Osteogenic Disorder Shionogi), dependent on dietary sources of vitamin C, to investigate whether reduced intake of the vitamin would differentially affect vascular function in late-pregnant (day 19) and age-matched virgin rats. The animals were given either 1 mg/mL of ascorbic acid ad libitum in drinking water [fully supplemented (FS)] or 0.25 mg/mL [marginally supplemented (MS)]. Fetal weights were 21% lower in MS than FS rats, whereas mean maternal weights and pup numbers did not differ. Small mesenteric arteries (diameter, 268+/-7 microm) were mounted in a pressurized arteriograph. Myogenic reactivity (contractile response to step increases in intraluminal pressure) was increased in arteries from MS pregnant compared with FS pregnant rats to levels observed in virgin rats. Ascorbic acid intake did not affect myogenic responses of arteries from virgin rats. Hence, the normal pregnancy-induced reduction in myogenic reactivity was abrogated in MS pregnant animals. Inhibition of nitric oxide synthase had no effect on the myogenicity of arteries from virgin or MS pregnant rats but increased myogenicity of FS pregnant rats to the level of MS pregnant rats. Free radical scavengers reversed the accentuated myogenicity of MS pregnant rats without affecting FS pregnant or virgin rat arteries. These data indicate that moderate ascorbate deprivation increases mesenteric artery myogenic responsiveness during pregnancy. This increase may result from a decrease in nitric oxide-mediated modulation of the myogenic contractile response.


Asunto(s)
Antioxidantes/farmacología , Deficiencia de Ácido Ascórbico/fisiopatología , Ácido Ascórbico/farmacología , Arterias Mesentéricas/fisiopatología , Complicaciones del Embarazo/fisiopatología , Sistema Vasomotor/fisiopatología , Administración Oral , Animales , Antioxidantes/administración & dosificación , Ácido Ascórbico/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Peso Fetal/efectos de los fármacos , Edad Gestacional , Cloruro de Metacolina/farmacología , Fenilefrina/farmacología , Embarazo , Ratas , Ratas Mutantes , Vasoconstrictores/farmacología , Vasodilatadores/farmacología , Sistema Vasomotor/efectos de los fármacos
17.
Br J Nutr ; 91(2): 227-34, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14756908

RESUMEN

The effects of dietary lipids on the fatty acid composition of rat pancreatic membranes and acinar cell function were investigated. Weaning rats were fed for 8 weeks on one of two diets which contained 100 g virgin olive oil (OO) or sunflower-seed oil (SO)/kg. Pancreatic plasma membranes were isolated and fatty acids determined. Amylase secretion and cytosolic concentrations of Ca(2+) and Mg(2+) were measured in pancreatic acini. Membrane fatty acids were profoundly affected by the diets; the rats fed OO had higher levels of 18 : 1n-9 (42.86 (sem 1.99) %) and total MUFA compared with the animals fed SO (25.37 (sem 1.11) %). Reciprocally, the SO diet resulted in greater levels of total and n-6 PUFA than the OO diet. The most striking effect was observed for 18 : 2n-6 (SO 17.88 (sem 1.32) %; OO 4.45 (sem 0.60) %), although the levels of 20 : 4n-6 were also different. The proportion of total saturated fatty acids was similar in both groups, and there was only a slight, not significant (P=0.098), effect on the unsaturation index. Compared with the OO group, acinar cells from the rats fed SO secreted more amylase at rest but less in response to cholecystokinin octapeptide, and this was paralleled by reduced Ca(2+) responses to the secretagogue. The results confirm that rat pancreatic cell membranes are strongly influenced by the type of dietary fat consumed and this is accompanied by a modulation of the secretory activity of pancreatic acinar cells that involves, at least in part, Ca(2+) signalling.


Asunto(s)
Grasas Insaturadas en la Dieta/farmacología , Páncreas/efectos de los fármacos , Amilasas/metabolismo , Animales , Calcio/metabolismo , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Relación Dosis-Respuesta a Droga , Ácidos Grasos/metabolismo , Fármacos Gastrointestinales/farmacología , Magnesio/metabolismo , Masculino , Aceite de Oliva , Páncreas/citología , Páncreas/metabolismo , Aceites de Plantas/farmacología , Ratas , Ratas Wistar , Transducción de Señal/fisiología , Sincalida/farmacología , Aceite de Girasol
18.
Am J Physiol Regul Integr Comp Physiol ; 283(2): R349-55, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12121847

RESUMEN

Administration of the ovarian hormone relaxin to nonpregnant rats vasodilates the renal circulation comparable to pregnancy. This vasodilation is mediated by endothelin (ET), the ET(B) receptor, and nitric oxide. Furthermore, endogenous relaxin mediates the renal vasodilation and hyperfiltration that occur during gestation. The goal of this study was to investigate whether myogenic reactivity of small renal and mesenteric arteries is reduced in relaxin-treated rats comparable to the pregnant condition. Relaxin or vehicle was administered to virgin female Long-Evans rats for 5 days at 4 microg/h, thereby producing midgestational blood levels of the hormone. The myogenic responses of small renal arteries (200-300 microm in diameter) isolated from these animals were evaluated in an isobaric arteriograph system. Myogenic reactivity was significantly reduced in the small renal arteries from relaxin-treated compared with vehicle-treated rats. The reduced myogenic responses were mediated by the ET(B) receptor and nitric oxide since the selective ET(B) receptor antagonist RES-701-1 and the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester restored myogenic reactivity to virgin levels. The influence of relaxin was not limited to the renal circulation because myogenic reactivity was also reduced in small mesenteric arteries isolated from relaxin-treated rats. Thus relaxin administration to nonpregnant rats mimics pregnancy, insofar as myogenic reactivity of small renal and mesenteric arteries is reduced in both conditions.


Asunto(s)
Arterias/efectos de los fármacos , Arterias/fisiología , Riñón/irrigación sanguínea , Relaxina/farmacología , Sistema Vasomotor/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Antagonistas de los Receptores de Endotelina , Endotelio Vascular/fisiología , Inhibidores Enzimáticos/farmacología , Femenino , Técnicas In Vitro , Bombas de Infusión Implantables , Óxido Nítrico Sintasa/antagonistas & inhibidores , Péptidos Cíclicos/farmacología , Embarazo , Ratas , Ratas Long-Evans , Receptor de Endotelina B , Grado de Desobstrucción Vascular/efectos de los fármacos , Vasoconstrictores/farmacología , Vasodilatadores/farmacología , Sistema Vasomotor/fisiología
19.
Lima; s.n; 2014. 34 p. ilus, tab, graf.
Tesis en Español | LIPECS | ID: biblio-1113623

RESUMEN

Introducción: Las lesiones extensas en miembro superior que implican pérdida de sustancia requieren cobertura, el colgajo inguinal McGregor es una buena alternativa para utilizar en estos casos. Planteamiento del estudio: Objetivo: Determinar la utilidad del colgajo inguinal McGregor en la reconstrucción de miembro superior. Material y Métodos: Se estudiaron pacientes 20 que ingresaron al servicio de cirugía de mano por sufrir lesiones severas de miembro superior que requirieron cobertura con colgajo McGregor. Resultados: Se estudiaron 20 pacientes de los cuales 15 sufrieron atricciones severas y 5 quemaduras graves. Hubo complicaciones en 2 pacientes que fueron la dehisencia y la infección. Conclusiones: El colgajo McGregor es muy útil para cubrir defectos en miembro superior y que ofrece muy buenos resultados.


Introduction Wide injuries in the upper limb that imply the loss of the substance require cover, McGregor inguinal flap is a good alternative to use in these cases. Study approach: Objective: Determine the utility of McGregor Inguinal Flap in the reconstruction of the upper limb. Material and Methods: 20 patients who entered to the hand surgery service were studied because they suffered severe injuries of the upper limb that require cover with McGregor flap. Results: 20 patients were studied in which 15 suffered from severe attritions and 5 from severe burns. There were complications in 2 patients, these complications were the dehiscence and infection. Conclusions: The McGregor flap is highly useful to cover the defects in the upper limb and offer satisfactory results.


Asunto(s)
Masculino , Femenino , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Procedimientos de Cirugía Plástica , Colgajos Quirúrgicos , Traumatismos de la Mano/cirugía , Estudios Observacionales como Asunto , Estudios Retrospectivos , Estudios Transversales
20.
Fontilles, Rev. leprol ; 19(4): 369-386, Ene.-Abr. 1994. tab
Artículo en Español | SES-SP, HANSEN, Hanseníase, SES SP = Acervo Instituto Lauro de Souza Lima, SES-SP | ID: biblio-1225681

RESUMEN

A partir de una muestra de casos de lepra detectados en el Estado de São Paulo, Brasil, entre 1943 y 1983, se describe y se avalúa la tendencia temporal de la endemis en el Estado. La tendencia de las tasas de detección ha sido estudiada por sexo y grupo de edad,. así como también las proporciones de las distintas formas clínicas, incluso por comparación con otros países de tendencia secular parecida. En el período estudiado, la tendencia global de las tasas de detección es decreciente; sin embargo, solamente las dos décadas subsiguientes a la introdución de la sulfonoterapia podrían considerarse como de caída real la incidencia. Dado que el lapso abarcado incluye límites importantes en la terapéutica y el enfoque de las políticas de control de la lepra, se intenta una interpretación del fenómeno epidemiológico observado en función de las características organizativas y estratégicas del programa de control en las diferentes etapas consideradas.


Asunto(s)
Brasil/etnología , Diagnóstico , Lepra/etnología , Lepra/historia
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